Employee Benefit Plans Employee Benefit Plans: The Components of Net Periodic Postretirement Benefit Costs (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended			9 Months Ended	12 Months Ended		9 Months Ended	12 Months Ended		9 Months Ended	12 Months Ended
	Dec. 31, 2012 Successor [Member] Non-Union Pension Plan [Member]	Dec. 31, 2012 Successor [Member] Union Pension Plan [Member]	Dec. 31, 2012 Successor [Member] Retiree Medical Coverage Plan [Member]	Sep. 23, 2012 Predecessor [Member] Non-Union Pension Plan [Member]	Dec. 31, 2011 Predecessor [Member] Non-Union Pension Plan [Member]	Dec. 31, 2010 Predecessor [Member] Non-Union Pension Plan [Member]	Sep. 23, 2012 Predecessor [Member] Union Pension Plan [Member]	Dec. 31, 2011 Predecessor [Member] Union Pension Plan [Member]	Dec. 31, 2010 Predecessor [Member] Union Pension Plan [Member]	Sep. 23, 2012 Predecessor [Member] Retiree Medical Coverage Plan [Member]	Dec. 31, 2011 Predecessor [Member] Retiree Medical Coverage Plan [Member]	Dec. 31, 2010 Predecessor [Member] Retiree Medical Coverage Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Service Cost	$ 1,326	$ 492	$ 176	$ 3,091	$ 3,709	$ 3,461	$ 1,251	$ 1,422	$ 1,325	$ 424	$ 555	$ 522
Defined Benefit Plan, Interest Cost	423	244	639	1,089	1,478	1,398	725	1,214	1,391	1,817	2,613	2,589
Defined Benefit Plan, Expected Return on Plan Assets	(550)	(332)	(631)	(1,301)	(1,545)	(1,240)	(970)	(1,517)	(1,334)	(1,596)	(2,330)	(2,136)
Defined Benefit Plan, Amortization of Gains (Losses)	0	0	0	835	512	386	342	202	122	2,468	1,758	1,580
Employee Transfers	0	0		32	121	(24)	(32)	(121)	24
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements		(1)					2,467	778	1,209
Defined Benefit Plan, Other Costs	363	595	(184)	487	475	(301)	(1,076)	2,772	2,172	(3,113)	(2,596)	(1,644)
Defined Benefit Plan, Net Periodic Benefit Cost	$ 1,562	$ 998	$ 0	$ 4,233	$ 4,750	$ 3,680	$ 2,707	$ 4,750	$ 4,909	$ 0	$ 0	$ 911

An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Return on Plan Assets

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Name Statement of Financial Accounting Standard (FAS)

-Number 87

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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-Name Statement of Financial Accounting Standard (FAS)

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+ Details

- Definition

The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

+ References+ Details

- Definition

The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph a, h

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Service Cost (Component of Net Periodic Pension Cost)

-URI http://asc.fasb.org/extlink&oid=6525008

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 87

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 106

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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-Section 50

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-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

+ Details

SOUTHERN STAR CENTRAL CORP 10-K/A